Maybe It's a silly question... Do I need to apply 5V power to the buttons to make them function?

I breadboarded out a controller with buttons that bridge back from the GPIO pin to ground. Some of the buttons worked, others didn't. I was concerned on those that did not work that I maybe had a wiring issue or bad connection on my button, so I tried manually connecting the IP pin to my ground as a button press, and still got nothing.

Was using a Raspberry Pi 3B+

The only buttons that worked were connected to BCM 0, 5, & 6. I was using the ground from pin 39 for all the buttons.

I didn't install onto a clean RetroPie build, but it was pretty close to clean. I'm using the Raspberry Pi official 7" touchscreen, my retropie build has a few skins, and I ran the retropie update on it at one point in time. That's it. I didn't have any errors or anything when going through the setup.

Maybe It's a silly question... Do I need to apply 5V power to the buttons to make them function?

I breadboarded out a controller with buttons that bridge back from the GPIO pin to ground. Some of the buttons worked, others didn't. I was concerned on those that did not work that I maybe had a wiring issue or bad connection on my button, so I tried manually connecting the IP pin to my ground as a button press, and still got nothing.

Was using a Raspberry Pi 3B+

The only buttons that worked were connected to BCM 0, 5, & 6. I was using the ground from pin 39 for all the buttons.

I didn't install onto a clean RetroPie build, but it was pretty close to clean. I'm using the Raspberry Pi official 7" touchscreen, my retropie build has a few skins, and I ran the retropie update on it at one point in time. That's it. I didn't have any errors or anything when going through the setup.

No you do not. You just have to connect the GPIO pin to a GPIO ground completing each circuit per button press.

hello ! im so close i feel...
this works upon entering the command
" sudo ./retrogame "
i can navigate through the retropie menu and play games with working buttons.
however after entering the command to have it launch automatically on boot ;
" /home/pi/Adafruit-Retrogame/retrogame & "

it does not take effect and i have to re enter " sudo ./retrogame " to have button function back..

im using a Pi zero w with a common ground 4 button pcb.. so close ! THANKS!